/Engine/Source/Editor/MovieSceneTools/Public/TrackEditors/SubTrackEditor.h
Get theUMovieSceneSubTrackclass
virtual [TSubclassOf](API\Runtime\CoreUObject\Templates\TSubclassOf)< [UMovieSceneSubTrack](API\Runtime\MovieScene\Tracks\UMovieSceneSubTrack) > GetSubTrackClass() const